1 /* SPDX-License-Identifier: GPL-2.0+ */
2 /*
3  * Copyright 2014 Freescale Semiconductor, Inc.
4  */
5 
6 #ifndef _RSA_MOD_EXP_H
7 #define _RSA_MOD_EXP_H
8 
9 #include <errno.h>
10 #include <image.h>
11 
12 struct udevice;
13 
14 /**
15  * struct key_prop - holder for a public key properties
16  *
17  * The struct has pointers to modulus (Typically called N),
18  * The inverse, R^2, exponent. These can be typecasted and
19  * used as byte arrays or converted to the required format
20  * as per requirement of RSA implementation.
21  */
22 struct key_prop {
23 	const void *rr;		/* R^2 can be treated as byte array */
24 	const void *modulus;	/* modulus as byte array */
25 	const void *public_exponent; /* public exponent as byte array */
26 	uint32_t n0inv;		/* -1 / modulus[0] mod 2^32 */
27 	int num_bits;		/* Key length in bits */
28 	uint32_t exp_len;	/* Exponent length in number of uint8_t */
29 };
30 
31 /**
32  * rsa_gen_key_prop() - Generate key properties of RSA public key
33  * @key:	Specifies key data in DER format
34  * @keylen:	Length of @key
35  * @prop:	Generated key property
36  *
37  * This function takes a blob of encoded RSA public key data in DER
38  * format, parse it and generate all the relevant properties
39  * in key_prop structure.
40  * Return a pointer to struct key_prop in @prop on success.
41  *
42  * Return:	0 on success, negative on error
43  */
44 int rsa_gen_key_prop(const void *key, uint32_t keylen, struct key_prop **proc);
45 
46 /**
47  * rsa_free_key_prop() - Free key properties
48  * @prop:	Pointer to struct key_prop
49  *
50  * This function frees all the memories allocated by rsa_gen_key_prop().
51  */
52 void rsa_free_key_prop(struct key_prop *prop);
53 
54 /**
55  * rsa_mod_exp_sw() - Perform RSA Modular Exponentiation in sw
56  *
57  * Operation: out[] = sig ^ exponent % modulus
58  *
59  * @sig:	RSA PKCS1.5 signature
60  * @sig_len:	Length of signature in number of bytes
61  * @node:	Node with RSA key elements like modulus, exponent, R^2, n0inv
62  * @out:	Result in form of byte array of len equal to sig_len
63  */
64 int rsa_mod_exp_sw(const uint8_t *sig, uint32_t sig_len,
65 		struct key_prop *node, uint8_t *out);
66 
67 int rsa_mod_exp(struct udevice *dev, const uint8_t *sig, uint32_t sig_len,
68 		struct key_prop *node, uint8_t *out);
69 
70 #if defined(CONFIG_CMD_ZYNQ_RSA)
71 int zynq_pow_mod(uint32_t *keyptr, uint32_t *inout);
72 #endif
73 
74 /**
75  * struct struct mod_exp_ops - Driver model for RSA Modular Exponentiation
76  *				operations
77  *
78  * The uclass interface is implemented by all crypto devices which use
79  * driver model.
80  */
81 struct mod_exp_ops {
82 	/**
83 	 * Perform Modular Exponentiation
84 	 *
85 	 * Operation: out[] = sig ^ exponent % modulus
86 	 *
87 	 * @dev:	RSA Device
88 	 * @sig:	RSA PKCS1.5 signature
89 	 * @sig_len:	Length of signature in number of bytes
90 	 * @node:	Node with RSA key elements like modulus, exponent,
91 	 *		R^2, n0inv
92 	 * @out:	Result in form of byte array of len equal to sig_len
93 	 *
94 	 * This function computes exponentiation over the signature.
95 	 * Returns: 0 if exponentiation is successful, or a negative value
96 	 * if it wasn't.
97 	 */
98 	int (*mod_exp)(struct udevice *dev, const uint8_t *sig,
99 			   uint32_t sig_len, struct key_prop *node,
100 			   uint8_t *outp);
101 };
102 
103 #endif
104